OBJECTIVES: 1) The release of free fatty acids by synaptosomal fractions in the presence and absence of serum albumin will be studied in an atempt to investigate whether the stimulatory effect of albumin on proline/histidine uptake is due to the binding of fatty acids by albumin. Attempts will also be made to establish the presence of fatty acid binding protein(s) in synaptosomal subfractions in general and the soluble synaptosomal fraction in particular. 2) The nature of inhibition of synaptosomal amino acid transport by dibucaine (nupercaine) will be investigated in greater detail. Possible relationship between such an inhibition and inhibition of phospholipase(s) by neupercaine will be studied. 3) The effects of other known fatty acid binding proteins on the transport of synaptosomal amino acids (proline/histidine in particular) will be investigated. 4) The effects of albumin on the transport of several putative neurotransmitters will be investigated with a view to establishing whether the stimulatory effect of albumin is general for the transport of neurotransmitter substances.